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National Emission Standards for Hazardous Air Pollutants Compliance Monitoring

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National Emission Standards for Hazardous Air Pollutants (NESHAPS) are stationary source standards for hazardous air pollutants. Hazardous air pollutants (HAPs) are those pollutants that are known or suspected to cause cancer or other serious health effects, such as reproductive effects or birth defects, or adverse environmental effects.

EPA develops national priorities that focus on significant environmental risks and noncompliance patterns. For Fiscal Years 2005 to 2007, the Clean Air Act: Air Toxics national priorities strategy focuses on categories of sources that emit HAPs.

NESHAPs are found in 40 CFR Parts 61 and 63. Part 61 NESHAPs regulate only 7 hazardous air pollutants:

The 1990 Clean Air Act Amendments, significantly expanded EPA’s authority to regulate hazardous air pollutants. Section 112 of the Clean Air Act lists 188 hazardous air pollutants to be regulated by source category.

The NESHAPs promulgated after the 1990 Clean Air Act Amendments are found in 40 CFR Part 63. These standards require application of technology based emissions standards referred to as Maximum Achievable Control Technology (MACT). Consequently, these post-1990 NESHAPs are also referred to as MACT standards. The NESHAPs are delegated to the states but both EPA and the states implement and enforce these standards.

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Compliance Monitoring Program

EPA conducts inspections of facilities subject to the regulations to determine compliance. EPA inspections include:

See The Implementation Tool Miscellaneous Organic Chemical Manufacturing NESHAP and The Inspection Tool for the Miscellaneous Organic Chemical Manufacturing NESHAP for inspection protocols which have been developed for the Miscellaneous Organic Chemical Manufacturing NESHAP and the Miscellaneous Coating Manufacturing NESHAP, respectively.

Sources subject to NESHAPs are required to perform an initial performance test to demonstrate compliance. To demonstrate continuous compliance, sources are generally required to monitor control device operating parameters which are established during the initial performance test. Sources may also be required to install and operate continuous emission monitors to demonstrate compliance. Consistent with EPA’s Clean Air Act Stationary Source Compliance Monitoring Strategy (PDF) (14 pp, 71K, About PDF), NESHAP sources that meet the Clean Air Act definition of “major source” generally receive a full compliance evaluation by the state or regional office at least once every two years.

EPA issued National Stack Testing Guidance (PDF), September 2005 (20 pp, 225K, About PDF) to address issues associated with the conduct of stack tests, such as

The guidance is not a regulation, nor is it intended to change any underlying regulatory requirements specified in individual NSPS, NESHAP, MACT, state or local regulations. The guidance merely documents and clarifies existing regulatory requirements and Agency guidance on stack testing. This final guidance supersedes the February 2, 2004 interim guidance.

For additional information on NESHAPs, MACT standards and hazardous air pollutants, see the EPA’s Air Toxics Web site.

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Compliance Assistance | Compliance Monitoring | Compliance Incentives


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